121398889 has 2 divisors, whose sum is σ = 121398890. Its totient is φ = 121398888.

The previous prime is 121398881. The next prime is 121398917. The reversal of 121398889 is 988893121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 85877289 + 35521600 = 9267^2 + 5960^2 .

It is a cyclic number.

It is not a de Polignac number, because 121398889 - 2³ = 121398881 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (121398881) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60699444 + 60699445.

It is an arithmetic number, because the mean of its divisors is an integer number (60699445).

Almost surely, 2^121398889 is an apocalyptic number.

It is an amenable number.

121398889 is a deficient number, since it is larger than the sum of its proper divisors (1).

121398889 is an equidigital number, since it uses as much as digits as its factorization.

121398889 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 248832, while the sum is 49.

The square root of 121398889 is about 11018.1163998208. The cubic root of 121398889 is about 495.1516577783.

The spelling of 121398889 in words is "one hundred twenty-one million, three hundred ninety-eight thousand, eight hundred eighty-nine".